Create new identifier translation framework with unit tests

- Deprecate GraphSubjects...
- Remove deprecated methods from GraphSubjects
- Integrate new identifier translation system into HTTP layer
- Add reverse translation to HTTP API

Resolves: https://www.pivotaltracker.com/story/show/67618364
resolve acl issue where user with reader and writer roles can't read
Merge pull request #287 from ksclarke/acl-writer-68547530

resolves issue where user with 'writer' role can't list ACL

Resolves: https://www.pivotaltracker.com/story/show/68547530
Adding Link header referencing LDP#DirectContainer (fixes https://www.pivotaltracker.com/s/projects/684825/stories/69469226)
Updating LDP membership triples (fixes https://www.pivotaltracker.com/story/show/69469312)
Adding support for OPTIONS requests on nodes with appropriate headers specified by LDP (Fixes https://www.pivotaltracker.com/story/show/69467500)
Adding Last-Modified header with create/update timestamp when nodes and datastreams are created/updated (https://www.pivotaltracker.com/story/show/68301562)
Merge branch 'ldp-updates' of github.com:futures/fcrepo4 into ldp-updates